The present invention relates to well devices and more particularly to packers used in oil wells and to similar devices.
Well packers and similar well devices are used in oil and gas production to separate a well bore into two regions--the region above and the region below the packer. Since it is often only necessary to temporarily set a packer in a casing, many designs have been suggested for temporary or retrievable packers. Examples of retrievable packers are described in U.S. Pat. Nos. 3,398,795 (issued Aug. 27, 1978), 3,667,543 (issued June 6, 1972), 3,818,987 (issued June 25, 1974) and 4,151,867 (issued May 1, 1979). The principal disadvantage with previous designs for retrievable well packers is that they are expensive to manufacture or to use due to the large number of components. Many require special devices for actuation. Only a few provide for the passage of a wireline through the packer when operations must be performed in the region below the packer.
The primary object of the present invention is to provide a well packer which may be set in a casing by interconnecting the packer with a wireline gun, lowering the packer into the casing, and actuating the wireline gun.
Another object of the present invention is to provide a well packer which may be retrieved from a well by lowering a retrieving tool into the well until it encounters the packer, continuing to advance the retrieving tool a short distance, and then pulling upwardly on the retrieving tool without the need for rotational motion of the retrieving tool.
Still another object of the present invention is to provide a well packer which may be permanently or temporarily set in a well and in which the packer permits a large number of operation to be accomplished without requiring removal of the packer from the casing. The present invention accomplishes this by providing a large bore through the entire length of the packer.
The many objects, features and advantages of the present invention will become apparent to those skilled in the art when the detailed description of the preferred embodiments is read together with the drawings which are attached hereto.